The opener hums but the door doesn't move, or it moves a few inches and stops. On a house from this era, that's rarely the motor itself - it's usually the drive gear or the capacitor giving out under a cold start, especially if the door's torsion spring hasn't been serviced in a while and the opener is doing more lifting than it should. Some homeowners hear a grinding noise before it quits entirely; that's the sound of a stripped gear trying to catch. Others get a working light and a dead motor, which usually means the capacitor failed outright. Either way, running the opener repeatedly once it's struggling just finishes off the gear or the belt faster. If the door is hard to lift by hand with the opener disconnected, the problem isn't the opener at all - it's the spring, and no new opener will fix that.